Book Image

OpenStreetMap

Book Image

OpenStreetMap

Overview of this book

Imagine being able to create accurate maps that look how you want them to, and use them on the Web or in print, for free. OpenStreetMap allows exactly that, with no restrictions on how or where you use your maps. OpenStreetMap is perfect for businesses that want to include maps on their website or in publications without paying high fees. With this book in hand you have the power to make, alter, and use this geographical data in a collaborative way from anywhere on the Earth.OpenStreetMap was started because most maps you think of as free actually have legal or technical restrictions on their use, holding back people from using them in creative, productive, or unexpected ways. This book will allow you to take control of your own maps and use them smoothly. This book introduces the reader to the OpenStreetMap project and shows you how to participate in the project, and make use of the data it provides. No prior knowledge of the project is assumed, and technical details are kept to a minimum.In this book, you'll learn how easy it is to add your neighborhood to OpenStreetMap using inexpensive GPS equipment, or even no GPS at all. You'll find out how to communicate with other mappers working in the same area, and where to find more information about how to map the world around you.Once you have your area mapped, you'll learn how to turn this information into maps, whether for use in print or online, large or small, and with the details you want shown. The book describes several rendering methods, each suited to different types of map, and takes you through a tutorial on each one.
Table of Contents (17 chapters)
OpenStreetMap
Credits
About the Author
About the Reviewers
Preface
4
How OpenStreetMap Records Geographical Features
Index

Does it work?


The process of crowdsourcing geographic data is accurate. A 2008 study by Muki Haklay at University College London examined the OpenStreetMap data for the UK in general, and London in particular, and compared it to similar data from Ordnance Survey. Haklay found that where data existed in OpenStreetMap, 80% of it coincided with Ordnance Survey data for the same features. The average distance from an OpenStreetMap feature to an Ordnance Survey equivalent was six metres, less than the general accuracy of GPS positioning, and this didn't take into account the possibility of the Ordnance Survey data being inaccurate.

There were also large areas where there was no data in OpenStreetMap. The conclusion is that if there is a problem with OpenStreetMap data, it is one of completeness rather than positional accuracy. Everything that's there is in the right place, but not everything is mapped yet.

Another vote of confidence in the quality of OpenStreetMap's data comes from one UK local authority, Surrey Heath Borough Council, whose staff have mapped the area covered by the council, and is using OpenStreetMap maps on its website and internally. You will also find maps based on OpenStreetMap data on whitehouse.gov, the website of the President of the United States.